Shanghai issued an orange warning for hail. Which is more terrible, hail or rainstorm?

Current affairs On April 30th, the morning in Shanghai was sunny and the temperature rose, as if early summer was coming. However, what's the weather like since afternoon? Style? Start? Mutation? The Shanghai Central Meteorological Observatory issued three early warnings for reporting, namely yellow warning signal of strong wind, yellow warning signal of lightning and orange warning signal of hail. Affected by thunderstorm clouds, there will be 9- 1 1 thunderstorm gale in our city, and the wind direction will be northerly. It is estimated that there will be lightning activity in most areas of our city within 6 hours, and there may be hail weather in the central and southern areas of our city in the next 2 hours. This is also the first hail warning this year. Hail was observed from 2 1 to 14 in Lu Hua Town, west of Chongming Island, with the maximum hail diameter of 1 1.0 mm. At 22: 06, the Shanghai Central Meteorological Observatory issued an orange warning of hail, which mainly affected the central and southern areas such as Minhang and Fengxian. This is the first time that Shanghai has issued an orange warning of hail since 20 17. Meteorologists explained that the temperature in Shanghai soared in the past two days, which led to the accumulation of unstable energy in the air. Coupled with the spread of weak cold air to the south, it is prone to strong convective weather such as thunderstorms and hail.

In bad weather, hail or rainstorm, which is the most terrible and changeable is the weather. It may be clear in Wan Li in the morning, but it will turn into a thunderstorm and gale in the afternoon, and hail will roar down. This is what people often say about bad weather. In meteorology, bad weather refers to sudden, fast-moving, strong and destructive disastrous weather, mainly including thunderstorms, hail, tornadoes, local heavy rainfall, snowstorms and so on.

What are the hazards of hail and rainstorm?

Hail is a weather phenomenon, which is most common in summer or at the turn of spring and summer. It is some ice particles as small as mung beans and soybeans and as big as chestnuts and eggs. The water on the local surface is evaporated by the sun and then rises into the air. A lot of water vapor gathers and condenses into clouds. The relative humidity at this time is 100%. When it meets cold air, it will liquefy, and the dust in the air will condense, forming raindrops or ice crystals, which are getting bigger and bigger. When the temperature drops to a certain extent, the water vapor in the air will be supersaturated, so it will rain. If you encounter cold air without condensation nuclei, water vapor will condense into ice or snow.

Main danger: the hail is also very strong? Fatal force? This is related to its size. If the hail is 2 cm in diameter, the landing speed is about 20 m/s, which is equivalent to about 70 km/h; When the hail is 6 cm in diameter and weighs about 100 g, the landing speed can reach 30 meters per second, that is, the speed of 100 km per hour, which is equivalent to rushing to the ground at the speed of a high-speed Mercedes-Benz. For another example, an egg-sized hail falls from the height of 1km, and the impact force is almost equivalent to a few kilograms of flower discs falling from the balcony on the third floor! Are you sure about this electricity, cars, doors and windows, roof tiles? Suffering? Even killing a cow is not impossible. Every year, all parts of our country are hit by different degrees of hail. Especially in the mountainous and hilly areas in the north, the eastern part of the Qinghai-Tibet Plateau and the Yunnan-Guizhou area, the terrain is complex, the weather is changeable and there are many hail, which is very harmful to agriculture. Heavy hail destroyed crops and houses, injured people and killed livestock. Extraordinary hail is bigger than grapefruit, which will kill people, destroy a large area of farmland and trees, and destroy buildings and vehicles. It has powerful lethality. Hail disaster is one of the serious natural disasters in China.

Rainstorm is a weather phenomenon. The main condition of rainstorm is sufficient water vapor, which is formed by the strong upward movement of airflow and the instability of atmospheric structure. Long-term rainstorm is easy to produce stagnant water or runoff to flood low-lying areas, resulting in floods, especially in plateau and mountainous areas, which are most likely to induce secondary disasters such as landslides and mudslides, and bring serious harm to people's lives and property. It is also easy to cause flash floods, reservoir dam breaks, river floods, houses washed down, farmland flooded, and traffic and telecommunications interrupted, which not only affects industrial and agricultural production, but also causes serious economic losses.

Heavy rain will not only cause secondary disasters, but also bring great epidemics. Floods will cause sewers and barns to be flooded, sewage will overflow, and pathogens such as bacteria and viruses will spread everywhere. The drinking water source is seriously polluted, and the food is moldy and deteriorated after being flooded; The deterioration of the post-disaster environment is conducive to the breeding of mosquitoes and flies, which requires local governments to attach great importance to effectively disinfect the flooded environment and strengthen the circulation supervision of water source safety.

We all feel terrible about bad weather such as hail and rainstorm, but if we look at the secondary impact after the disaster, the harm of rainstorm is even greater. ?